Nathan Bransford had a great post the other day that spoke a little bit about the numbers that traditionally published authors have at their disposal to get an idea of how their books are doing. He writes:

As a traditionally published author I basically have two numbers I can look at: the Amazon sales ranks for the hardcover and Kindle editions, and my Bookscan number of copies sold (as provided by Amazon).

The Amazon number is fickle and clearly only reflects a portion of my sales. Bookscan also only captures a portion, usually estimated to be 70% of sales, and that percentage varies from title to title.

Now, I recently had the opportunity to poke a little further at Bookscan, thanks to a trial via Publishers Marketplace, and I can tell you that the 70% estimate of what sales they track can be wildly off. For instance, I just sent an author their first royalty statement for a YA novel, which indicated that the book had already earned out. If I look today on Bookscan on the exact same title, even though the royalty statement only showed sales through the end of April, Bookscan is still off by almost HALF.

That’s a lot. And when authors are desperately trying to figure out how their book is doing, it can be wildly deceiving.

Nathan makes a good point that even the numbers authors do have access to don’t really show the most interesting data, but what I’d have you bear in mind is that, most of the time, they’re not even complete with what they do show. Bear that in mind when you’re frantically checking your Amazon sales rank, or noting how many people have added your yet-to-be-published book to their To Read shelves on GoodReads. It’s information, sure, but it’s not the whole picture.